Lap



LAP. FILED APR. 2s. 1920.

-- A. 1. DE'WILLE.

mmf

Jan'. 2, 1923.,

. L/i//T/a/.ffesSES,A A gw ,//fl f Patented dan E, 'i923 maar ANTOINE JOSEPH DE WILLE, 01 SUTERSVILIE, PENNSYLVANIA.

' LAr.

Application led April 28,

To all 'whom/t may Gomera: .y

Be 1t known that l, ANTOINE, Josnrrr .Dn WILLE, a citizen of Belgium, and a resident of Sutersville, in the county or lestmore-- land and State of Pennsylvania, have made a new and useful improvement in Laps, of which the following is a specification.

My invention consists oi't' a lapping` tool f having an adjustable lapping face and provided with means for controlling the supply of lapping or cooling material thereto.

I illustrate my invention as applied to a lens grinding machineot the type shown and-described in my copending application Serial No. 291,657 altho l contemplate its use in other than spherical laps and in other industries besides glass grinding and polishing. i

In the drawings, Figure 1r is a vertical sectional view thru a lap and lens holding spindle and a lenswhich lis being ground. and Figure 2 is a top plan ot the lap shown in Figure 1. Fig. 3 is an enlarged view in longitudinal section of one or the elements entering intothe makeup of the device.

It will be understood by reference to the abovelnentioned application that the machine in which the lap-is used provides relativeirotation of the lap and lens holder.

A lens 1 is cemented on a holder` 2 andits convex, lower face is, presented to a concaveV 3. The lapping surface et the lap 3 consists of the slightlyconcave ends oi a number of elementshere shown as comprising a plurality or screws 4 which are adaptl ed to ,be so inserted inthe body of the lap 3 that their upper extremities project slightly above the body face and are so positioned about the lap area that each annular element ot the lens will contact with at least one lap element. The radius of curvature of the concaved ends of the elements 4 is preferably less than that of the bodjvv of the la 3 The holder 2 is mounted on a spindle 2 by means of a balland socket joint which eEects a flexible rcontact between the lens 'l and the lapping elements 4. This yieldable connection also permits the holder 2 and then lens l to rotate about the lens axis' and also about the lap axis,thus providing` varying lap contacts for a given point on the lens. One or the objects of my invention is to provide means for maintaining the spherical 1920. Serial No. 377,241.

curve of the eiective lapping surface and this object is attained by the manipulation of the adjustable elements 4 against a templet of the proper curvature. The extremities of the screws 4 are then adjusted to the surface of a sphere defined by the outline of the templet. This adjustment may be repeated as often as is necessary to provide for the wear of the lapping elements. An originallvcontour may thus be preserved without the heavy cost of renewing the entire lap as is the usual case where the. lapping surface is integral with the lapping tool. Each of the screws 4 is provided with a lock nut 5 to maintain it in adjusted position.

ln the illustrated use of my lap, it is customary to supply lapping material in a solution which may be washed off and replaced when its grinding properties are eX- hausted. ln some forms of laps it is the practice to charge the lapping surface with a lapping material by pressing the material into the lapping surtace.- My lap is adapted for use. in either method.

One of the adjustable elements 4 is shown with its upper extremity set below the surrace of body 3 as indicated at 6, thereby forming a reservoir for lapping material which may be withdrawn by the relative rotation of the lap and lens and tend to prevent exhaustion ot the lapping material from the lapping elements. It will be understood that a number of the elements 4 may be partially withdrawn for this purpose and they may be so scattered about the surface ot the lap as to effect a fairly even distribution of the lapping solution.

The lap 3 is mounted upon a hollow spindle 7. the interior wall of which is provided with a tapered thread 8. The interior diameter of the spindle 7 below threaded portion 8 is greater than that ot the threaded portion and is adapted to receive a plug 9. The unper end ot the plug 9 is threaded as at 10 for engagement with the threaded portion 8 of spindle 7,

The plug 9 is provided with a central longitudinal aperture 11 which drains the upper face of lap 3. The upper portion of the plug 9 is Jformed with intersecting cuts 12 which render the split portion of the plug compressible laterally. When the plug portion 10 is screwed into spindle portion 8, the tapered surface of the latter gradually compresses the four sectors of the plug which restricts the size of the aperture 1l.

l insert a pin l'ina transverse apertureiin plug l) 'for rotating the plug butany `other suitable turning` means may be employed.

lf the flow-of thc lapping-inaterial lieso-l sluggish that a restricted dra-in is unnecessary, plug S) may be removed. In som classes of Work, a cooling fluid is freely applied to lapping or polishing` tools andfinA such cases the removal of the plug 9 will permitof the free drainage of. the'itl-uidand mei-cial development and do knot Wish tov 4limit my future .use to the pfirticdlar form shown. f I contemplate the usual equivalents of the s creyvs 4 nhaving the same functions ,in the lappnstonl.

Having described myV invention in its preferredform, l noiv` claim: j l

l. 'In a llapping tool fortan objectfhaving Laspherica'l surface, abody member, a pluralityof elements each provided with alapping face and adjustably mounted upon said 'body so that their lapping faces are presented towards a common central point for movement.toward and from saidpoint.

E2. In aLlapping tooha body provided with a, curved Y'tace and a plurality of "lapping elements adjustably mounted on said body nach having; a curved Ilan tace of d'ierent .radins Of @n.l'vaturefrnni that of the carved tace of ythe body but .presented 'insubstantially the .Sanne direction- 3. -In ha lap, abody having a concave face to be presented towards the object to be ground, apluigality of element-s ac ljust'abjly mounted onrsaid body each having a concave lapping .face presented in the saine direction `as saidbody-face and means for retaining said elements in adjusted position.

4i. In a lapping tool, a hollow, mounting spindle, internally threaded, a lapping surface having a central hole alined Awith -Said spindle` and hollow, .compressibleV plug having ,fi-threaded exterior parisien adapted .te be screwed Ansainil .Spindle- .and compressed asadranned .ther-ein.

5;- .A 1an plnvded with a nlnralityn de iii-*entsinne inf its "lannina surfane .adapted lto retain asnrplr 0f lapping material .and provided with an adjustable means for determining the depth nti said depressions.

6. A lap provided with a Vdraining element for lapping material and means for adjusting the drainingcanaeitv of said elenneni-J i 7, .lapping boel, comprising a body hevng .al plurality of irregularly spaced helse drilled and 12a-pred therein, threaded inserts mounted in said holes and having their points shaped to form lapping' surfaces and projecting beyond the surface of said lbody@ and means for securingsaid `-screws in desired position.

8. ln a lapping tool adapted to be used WithTa-liuid lapping material, a body having a face adapted to be presented towards an article to be lapped and Which is provided with a plurality of recesses which extend inwardly lfrom said face, a plurality of elements mounted in said recesses each adapted ,to extend above said .face to form allap ping element or to be Withdrawn below said face to form, with its respective recess, a reservoir for lapping material and lmeans for securing said elements as desired.

9. A "lap .adapted 'to drain lapping material to a central pointandprovided with a drainage valve -located .at its central point, .and means `for Aadjusting the capacity of said valve. 1 j

10. .A lapping tool conrprisinga body member, a plurality of independently' adjustable lappingelements carried thereby and `means `for selectively securing said eleT ments in adjusted positions(abovef-andlbelovv I the surfaceof said 'body member.

l1. A llapping tool comprising a body member having a plurality/fof independently adjustable-lapping elements mounted theref on and irregularly disposedwith respect to each other. i j

l2. A lapping tool comp-risingn lap meinber, a tubular drain 'therefor and a ,valve member disposed Within saidtnbnlar drain to regulate the flow of lappingruaterial therethrough. Y' j v` 13. Alapping tool comprising alap niember. a tubular drain therefor havinga restricted opening communicating with the face of said lap yand a valve member `disposed in said tubular drain having a portion adapted to co-a-ctvvith` the lrestricted portion of said tubular .drain to Vregulate the flow of lapping material therethrough.

14. A lappingtool-comprising a lap member, al tubular drain therefor having arestricted opening` communicating with the surface of said lap and a. valve. member having acompressible portion adapted Atc cooperate with the restricted pcrtinl Vof said tubular drain. to regulatethe flaw .ofxlappng material therethrough.. 'j

15; A 'lapping tool Vcomprising a lappmeinber, atub-ular drain. ,therefor having a re-l lstlioted opening communieatingr with the surface of said. lap and a valve Vmember having aslotted portion adapted to co-operate with the vrestrictedportion of saidtubnlar drain and be compressed thereby to re- I stricted opening communicating with the surface of said lap and a valve member having a. plurality of: longitudinally extending fingers spaced -from each other to provide a passage-Way therebetween, the extremities of said fingers being adapted to engage said restricted portion of said tubular drain to move said fingers toward and awa-y ANTOINE JOSEPH DE WILLE. 

